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Like many others on this forum, I too am learning how to TIG. My best resource has been the TIG Handbook from MillerFirst shot is before I looked closely at the chart for amperage. Metal is 1/8" thick. 1/16" Red Tungsten, 1/16" filler rod. Argon to 15 cfm (or was that 10?). Current set at 40 amps. Obviously its way too low. Metal was ground on top only (not the back side) for the first four beads.Not quite sure what happened with that red flash. I know I contaminated the tungsten on that fourth bead. I suspect that I touched the tungsten with my filler rod. I got a flash of color, and from that point on, the arc turned different colors. Reminded me of the stuff that they used to sell that you would put on the logs in the fireplace, and it would burn all weird colors. You can see the contamination on the tungsten electrode in the photo. What is that red stuff? It wipes up easily. What causes that?I suck, really suck at running a straight line, I really drift... See that first bead? So I added a welders soapstone reference line to practice to, see bottom of the photo. Question: Will that contaminate the weld? This is more of a question for practice beads.. when welding two pieces of metal together, there is generally a very recognizable weld interface 'line'. Big Oops. Went and looked at that Miller manual again. I increased the current to 90 Amps. This seems much better, but I still have a LONG way to go in terms of practice. I am assuming that the defects in the weld bead are caused by mill scale contamination? (or is it possible that is from surface rust on my welding table?) Next step is to obtain some more practice blanks of metal to play with, and clean them up both sides before starting. One thing I'm not clear on is how much tungsten stick out should I be using? Photo shows how this was run. I spoke via phone to one of my TIG buddies (who is a few months ahead of me on the learning curve.) He recommended putting the electrode out there 3/8 to 1/2" of an inch and increasing the Argon flow to compensate. I have a gas lens or two, just haven't tried using them yet. Note: My ultimate goal is to learn how to TIG bicycle frames together.. and that metal is thin (0.8 or 0.9 mm)thanks for all assistance, zip Attached Images
Reply:I will take a few wild guesses as to what you're doing wrong. 1. You cannot really see the weld puddle very clearly for what ever reason. 2. The tunsten to work distance is much too large. Try keeping the tunsten at a consistent gap of 1/16", no more than 1/8". 3. Your travel speed is way too slow. 4. You're melting the filler with arc and letting it blob onto the base metal. You want to dip the filler into the puddle, let the puddle melt the filler.Make sure you can clearly see the puddle, get a better lens, try a shade 9 instead of a 12, get a magnifier or reading glasses. Now, try making a small weld without adding filler. Once you can make a uniform autogeneous weld, then try adding filler. Establish a small puddle, dip the filler in the puddle, retract the filler, move forward, repeat.Looking forward to your next set of pics.
Reply:Have you ever welded before? If not, I suggest that you look at some videos online that show the puddle through a welding lens so you know about what its supposed to look like. No reason to even try adding filler if your beads are looking like that. (No offense)Your way to hot, and since 90 amps might be a tad on the cold side for 1/8 material im betting its because you moved way to slow. Your bead is huge and the amount of burn though from the other side isnt acceptable. Focus on maintaining a nice, smooth and consistent weld bead w/o filler first.Have we all gone mad?
Reply:Originally Posted by zipzitLike many others on this forum, I too am learning how to TIG. My best resource has been the TIG Handbook from Millerzip
Reply:On top of what they already said i found it easier to learn with a bigger cup. The smaller cup is harder to keep the rod in coverage when you are first learing. (not that that is your current issue but it will help after you get the basics)1995 supra 6-speed. 9.91 @148 mph on e85
Reply:I'm a beginner too. Here's a thread I posted about much the same thing. http://weldingweb.com/vbb/showthread.php?t=39279I did finally have some luck and produced a fillet weld that was passable...at least to me. I listed the material specs and machine settings I used if that's any help to you.Good luck and keep at it....if I can do it anybody can...just maybe not the first time.Miller 211 w/ spool gunMiller Dynasty 200DXLongevity 60i IGBT plasmaO/A w/ crappy chinese torch/gaugesSouth Bend 10K latheGrizzly 4029 10x54 millGrizzly 7x12 hor bandsawangle grnders, bench grnder, bench belt sndr7.5 hp 80gal cmprsor
Reply:Are you welding where their is a low light source or with a helmet that does not have any adjustment to the lcd lens by any chance because I have the same thing happen to myself when I go to weld something quick and don't setup properly.
Reply:Folks thanks for the feedback so far.--I know the first lines of bead are really terrible.. I was more playing around than not, and I certainly would NOT have included them here, but for two questions (neither of which has yet been answered... hint, hint!)1) What is that red stuff on the first photo?2) Is it okay to TIG over welder's soapstone?I've prepped some more metal tonight.. frigging mill scale is tough stuff. I know you are supposed to clean up both sides of the metal, but what happens to the inside of square tubing? Isn't there mill scale inside? I will run some beads tomorrow. I do have some 3/32" gold tungsten, but I only have 1/16" feeder rod. I can double up on my feeder rod. Miller TigBook Chapter 6 says for 1/8" thickness mild steel, use 3/32 or 1/16" tungsten, 3/32 filler, 90-115 amps, 15 CFH inert gas for fillet / lap joint.. I'm thinking I will start at 110 amps, adjust with foot pedal?No offense taken on any constructive criticism. Many thanks for the tips.. (Lets just see if I can take hold of this...) --zipLast edited by zipzit; 03-18-2010 at 09:53 PM.
Reply:Don't even use Filler yet.Cut up some coupons and butt weld them w/o filler so you can control the puddle first.Then buy the correct filler.Oh- not sure on the Red stuffOk to weld over Soap Stone.Ed Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:The red stuff is from when you contaminated your tungsten. You got a layer of steel on it. Steel can't stand up to the heat that tungsten can, so it burns and vaporizes in the arc. Then it collects on the work piece leaving the red residue. When you contaminate a tungsten the way you described jut stop what you're doing and go regrind it. When it's contaminated the arc characteristics are all messed up, plus you'll probably notice you filler wire hand getting warmer, I think the super heated steel on the elctrode puts out more UV radiation than a clean tungsten.As for the soapstone, it should be ok to weld over it if it's just a guid line. Filler materials have cleansers in them (usually silicon) to help remove minor impurities. But you really need to clean the millscale off befor you weld. You'll find it'll be easier to weld, you wont see the silicon deposites like you do in pic #2, and when you get into fillet welds it will help prevent undercut.
Reply:I'm just a beginner here too and have been using a Lincoln TIG slide rule setup to get my settings and other weld info.This slide rule gives you all of the settings and correct electrode/cup/filler rod sizes for a given material thickness/weld type (9 types of welds listed) /material type. It also gives you the correct weld speed in inches per minute and about all the relevant data you should need.This little slide rule definitely gets you in the ballpark. An experienced pro welder tells me that he uses the settings/sizes from the slide rule all the time and rarely needs to stray from them.Glen
Reply:The beginner saga continues... Here's what I learned today:I wasn't happy with my supply of practice steel. I visited a new local steel supply place (Astro Steel in Centerline MI). Small industrial fab & steel supply place. Met the owner, he was the guy in the funky-sunburnt-from-welding-clothes running the beat up fork lift. Nice guy. I'll be going back there.Picked up some scraps of 1/8" and 1/16" sheet steel. Took that stuff home to clean off the mill scale. Dang was that work! I ended up using my 4.5" grinder to do most of it. Got the metal shiny clear on both sides, polished it up with an angle die grinder with small sanding disk. Cleaned the metal both sides with rubbing alcohol, cause that's what I had available. While I was at it, I did a quick run with the sanding disk on top of my welding table. Lots of brown rusty stuff came off. Its not totally shiny, but way cleaner than before. Wiped the table top with alcohol as well. Set up as follows: 3/32" gold tungsten, ground fresh. 100 amp setting, #6 cup (the largest that I had..) 15cfh argon. DCEN. 1/8" thick steel plate, ground shiny both sides.Lessons learned. Learn to See the puddle... Had a bit of a struggle with the helmet settings. Ran a few beads to get that straightened out. I know did run at least one bead with the helmet in nearly clear mode. Ooops. Couldn't focus on anything for ten minutes after that. Helmet settings need to be Sensitivity: Nearly all the way to high (NOT the OTHER WAY, ugh.) filter: 9.5 All of these shots are without any filler at all. Runs #4 thru #8 made with helmet in correct mode. #4, tungsten stick out = 3/8" #5 , tungsten out = 5/16" #6, same as #5.For these three runs, I pretty much had full pedal without much change. I modulated things with torch speed (and be gentle here.. I'm a new guy to this, and I'm not quite clear on what the target is suppossed to look like.)In run #7, I remembered that the pedal can move.. I was trying to correlate foot pedal to flame view to puddle view... Hence the stutter stop / start at the beginning of that bead. At one point the puddle got quite hot and agitated. Stuff started to boil, and I'm quite sure a molten drop hit the tungsten. I KNOW that I did NOT dip the tungsten towards the work, I was extremely careful about tungsten height above the work for that run. Its pretty clear on the photo where that happened. I get the famous red flash again (and Grimm, your description of what is happening makes good sense...)#8, regrind tungsten, run again. stick out = 3/8" And this run was more interesting. I noticed that as the puddle just hints at getting agitated, there is a noticable hiss noise. When that noise just started to get loud, I'd back off on the foot pedal. Not sure if that is right, but it felt right.Last run was a no filler butt weld. I didn't grind it as well as I should have.. I did a quick grind on the bench grinder and it didn't do a very good job of surface clean up. I ended up with a wide bevel on top and bottom of the piece. Not sure if the photo shows it well, but the piece with the cursory surface grind (read that, still has lots of mill scale on it..) shows a much deeper undercut than the other side of the joint. (Grimm, on the cleanliness to undercut correlation, again, good call!) I didn't include a measuring scale in the photo, but that weld 'bead' is 1/4 to 5/16" in width. Photo of backside indicates things got hot, but not nearly as hot as before. The backside of the no-filler butt joint, assembled tight, indicates incomplete penetration except at the points of tack welding. Should I go hotter (or leave a slight gap next time, oxy/acetylene style..)More comments? What should my next steps be? (I'm thinking cutting up some more blanks with proper surface cleaning and then run a few more no filler butt joints.. but from there where should I go?)With a no filler surface or butt joint, what should I be trying to achieve?Oh, and one more thing that I noticed today. My 3/4" thick table top is highly magnetic. Stuff really sticks to it. Not sure if that matters or not, but its definitely magnetic.thanks in advance to all for your comments.zip. Attached ImagesLast edited by zipzit; 03-19-2010 at 08:50 PM.
Reply:Back of the work piece looks fine to me. You're going to have discoloration, and even a little scale flaking off. The sputtering you described is confusing. I've seen it when working with castings due to impurities in the metal, but I can't imagine why you were getting that with hot rolled steel. Did it just start doing that in the middle of a pass? Or was it at one of your starts? And yes, when it starts bubbling like that blobs of steel will jump out at your tungsten, You may also find B.B.s stuck to your gas lens if you're using one.The butt weld looks half decent. Though it did get a little too hot. You were probably moving too slow. common mistake for new weldors. Practice will help you pick up the pace. Higher heat with a faster travel speed would allow you to penetrate all the way through the joint without getting the over heated look you have on that weld. It'll come with practice. Just keep running beads untill you're sick of them, then run some more. Try bumbing the heat up some more, say 125, see how that runs for you.As for the magnetized table, that will happen when you're doing alot of welding on a thick metal surface. Let it set a little while, the magnetizm usually doesn't last. I have a work bench with a 4" thick top. It can get pretty magnetized when I'm flying through parts. Reminds me to stop and take a break.
Reply:I had to register just to comment on this thread - I've been a long-time lurker.Last fall I bought a Diversion 165 and thought I could learn to Tig on my own. I couldn't. My welds looked way worse than those at the beginning of this thread. I've been taking some classes and gotten much better, and now I can lay down a bead that looks OK - not good, but OK.Having just been through it, I will comment on what I see. First - I agree with the above commenter that you may not be seeing the puddle correctly - I had trouble with this, and I had trouble making the torch "push" the puddle along the base metal. I found I had to move my head further to the side, so I could see the puddle better - I had been looking from above and only seeing the arc. You have to be able to actually see the puddle move along the surface- in aluminum it gets mirror shiny when it melts - then you can dip the rod into front edge of it. Second, I think you may have too much heat, but you are probably also holding the torch way too high above the surface - it needs to be really close - I mean really close - without dipping. It required much more precision than I had anticipated. I found I had a great deal of trouble steadying my torch hand enough to keep it the right distance - I finally learned to see the puddle and the relationship of the puddle to the torch tip.Another thing I learned, that may be affecting your welds is the diameter of the rod - I was using 3/16 rod, and should have been using 1/8 - it helped a bunch when I got the right size rod.PS - something else I did wrong was I was trying to use a bad auto dark helmet - It seemed to not be darkening enough, and blinding me - then darkening too much and either way, I was losing the puddle. I just went with the el cheapo fixed dark helmet and it was much better.Last edited by Indywelder; 03-20-2010 at 03:03 AM.Reason: added ps
Reply:I am still learning tig myself but for the most part I found fairly easy to get puddle control and bead profile. I guess it could be found the years of welding stick and mig. The pictures you posted look more like stick beads to me. I am no expert but something sure seems off. What I found was using a gas lens and a number 6 or 7 cup you can run a decent stick up with the tungsten. This allows you to see the puddle very easy and add filler. It also saves on gas usage as you you find the argon tanks never seem to last long enough. I also use the 1.5% lanthanated tungstens ( gold ) which I find very nice to work with. My tig came with a red but I prefer the gold. It holds a very sharp point and makes a nice fine arc. Since sheet metal is my main gold for tig, I run a 1/16 tungsten or a 3/32. I prefer the 1/16 for the thinner material. Try dealing with no thing at a time. Work on puddle control then start added filler. seat time is whats going to help you work it all out.Miller DVI2Lincoln Precision Tig 225Thermodynamics Cutmaster 38Everything else needed.
Reply:oops - I bet I meant to say 1/16 rod and 3/32 rod istead of 1/8 and 3/16.Either way, the thinner rod is better to learn with.
Reply:Originally Posted by Grimm1I have a work bench with a 4" thick top.
Reply:For steel or stainless steel I always try to use a gas lens. To be honest, a 3/32" tungsten for 1/8" steel is probably a little better. You can come on and off the heat more extremely. Causing deep penetration without the severe heating. A midrange setting on an older transformer welder. Probably about 0-200 on a new welder. Sincerely, William McCormick
Reply:Originally Posted by 66myndwow why so thick?
Reply:Haven't forgotten about you guys... I'm sticking with 3/32" gold tungsten, amps around 100. I did end up purchasing a non automatic welding hood, with a #10 filter. I've picked up real 3/32" welding rod. I haven't made it back to the good weld shop to pick up the white gaskets for the gas lens. I will say, I'm very unhappy with my progress... so much so that I'm not posting photos. Note: I did take a break from TIG practice to finish up my welding table. I will say I've gotten quite confident with my stick welding abilities on the table project. (Is that a result of recent TIG practice?) I need to get the table done and on wheels so we can park cars in the garage again.Question.. I've looked long and hard on the web trying to find photos of TIG nirvana. Here's what I came up with...ref: http://waltworks.blogspot.comWaltworks Bicycle ForkI really am not getting this. My practice beads look like really good stick welding beads.. but too large for TIG stuff. I'm not really clear on how Walt (of Waltworks Cycles, welder of that bicycle front fork) is getting these beads. Is that a step and pause motion, or is that bouncing on the footpedal or even a machine pulser function.. ? (I'm pretty sure it's not the machine pulser, as Walt has been pretty verbal against that practice in the past.) When you look at a practice TIG bead (initially with NO Filler) how do you judge what is good? On a scale of 1 to 10, how important is:Consistency of 'bead' width?the overall width of bead (too narrow? too wide?)stacked dimes / stepped look to the 'bead'size of the heat affected zone?penetration as evidenced by view of the backside of a piece of metal?consistency of bead itself (cleanliness, no holes, voids, signs of inclusions..)I think for me welds like that bicycle front fork are the ultimate goal.. Do you guys agree? Does anyone have a photo of a better tig bead on steel as a target goal of TIG nirvana? I'm reducing my variables to focus on one thing at a time, I'm just not sure which of the above elements I should be focusing on. I do realize I'm in for a long, long haul. I'm trying to focus on a consistent narrow width bead, and that means a very small weld gap (causing me to frequently contaminate the electrode.) I will say I'm getting VERY adept at using the grinder, so much so that I have now been able to sharpen 1/8" drill bits by hand very successfully. (I've been doing lots of pilot drilling in 3/4" steel on the table project.)Thank you for your input!--zip Attached ImagesLast edited by zipzit; 03-30-2010 at 12:13 AM.
Reply:I think that the correct weld on different metals all look slightly different. I'm not sure what the material is that you have pictured but I believe that if you have, for instance, a fit up like that out of mild steel and one out of aluminum that after being welded correctly they would be different looking welds. I wouldn't get too crazy trying to get a stack of dimes effect when in fact it might not be what the weld naturally looks like on that particular metal. I just hooked up my tig and have been practicing also. I can weld all position stick with my eyes closed and I can mig as well. But tig is tough and its all about practice, I can get a really nice consistent flat weld on mild steel but beyond that I suck still. Sometimes I think, will I ever be able to weld all position thin material... but you just gotta keep doing it. I do notice that, at least for me, my flat tig welds on mild steel don't look the same as what you have pictured. It looks more similar to a 7018 weld but nicer. I am reading the miller tig book and I got the settings chart also, so I make sure every variable is set accordingly and then I make sure that I am holding the torch at the right angle and be as systematic as I can in making the weld. It looks great but its no stack of dimes so to speak.But thats just my two cents. Look forward to seeing your progress, post some pics.
Reply:I'm back. Still working on this. I'm trying to run 10 or 12 beads practice each day. Oh, and I'm pretty anal (but you probably already knew that..) I'm keeping detailed notes on what I'm doing, as I'm going. I'm hoping that may help others in the future who get to this same point.--I cleaned up steel with grinder, got rid of all mill scale. I just used a 4.5" grinder for that.--I struggled with lots of backlighting in the shop reflecting off the inside of my helmet. I figured out a way to do a bright spotlight that shines on the work tabletop, but not reflect in my eyes.--Tonight I did a lot of torch off static practices to get a feel for the motion of my guide hand. (Kind of like dry target practice I did when I was a kid, when first learning how to shoot a rifle.) I often felt like my hand would slide on the table, then once in a while get stuck and screw me up. What I discovered in that practice was that I could control things better if I abandoned my over hand grip (like holding a steak knife to cut a tough piece of meat) and went instead to a pencil grip on the center of the handle extension. It changes the angle of the tungsten somewhat but generally seems more accurate for maintaining a consistent and small arc length. I also discovered that for consistency it helps to drape the TIG hose over my left shoulder (I am right handed.)--Trials #1,2: 3/32 filler rod, slow speed. The filler rod seems like too much metal to add for a flat plate exercise. blah!--#3, straight bead, no filler..#4,#5 I thought I'd try a 1/16" filler rod. With these conditions (flat plate, straight bead practice) this seems to be more consistent to add to the puddle. These runs seem too cold. There is not good wet out / tie in on the edges of the bead. Bead width of #4 measures at 1/8"--#6, I changed my grip to add a l more torch angle in the direction of travel, in the direction to 'push' the puddle. Yowza! Not sure what happened but this made a pretty big difference. This bead just said "Run me fast." So I know this bead was run at a higher travel speed, with a little more pedal than previous. It also gave me more puddle ahead of the tungsten with which to dip the rod into. Note: I am doing a step, slight pullback and pause with my right hand. When right hand pulls back, left hand moves forward to just touch the leading edge of the puddle with the filler rod during these runs. Run #6 looked pretty good to me.. fairly consistent width, penetration seemed good (no sign of burn thru, just the dull gray line on the backside.) I was like, wow, I'd be happy if I could make four or five more beads just like #6. --#7-9, same as #6. Run with a step and pause motion.#10,11.. I tried running these last two beads with a smooth consistent motion, withOUT step and pause. There was enough weld puddle ahead of the tungsten arc that I could still dip the filler and not contaminate the tungsten. Obviously I still have LOTS of opportunities for improvement, but I think I'm making some progress. I'm thinking I'm almost ready to start putting pieces together (so back to 3/32" filler rod.) I do know I need to figure out how to start adding filler earlier in the process...One question.. after I put stuff away, I did a search online to try to understand how to best hold the torch. I did see one tutorial that recommended a pencil grip, right around the neck of the torch, right up against the cup. Do you guys really do that? Doesn't the cup get pretty hot? (See photo at http://www.customclassictrucks.com) It looks like a way to add another level of consistency to a reduced arc length, but that makes me nervous. I'm using some funky old style heavy terrycloth cotton welding gloves that I picked up decades ago for stick welding. I'm thinking I'm going to burn my fingers off with that grip. I guess I'll try it tomorrow and see what happens. (Note: photo of pencil grip shown here is from customclassictrucks.com, not my original)As always, thanks to all for your observations and comments.--zip Attached Images
Reply:Pretty sure Walt uses a Dynasty. If you're familiar with his blog, frameforum, phred, mtbr etc... you may have read that he stated using a Maxstar for his first 100 or so frames, and regretted switching to the Dynasty because the Maxstar did it's job well for framebuilding.Don't know which one was used for the segmented fork you posted.Look for Groovy Cycleworks blog if you want to see great welding, and pick up some great knowledge/pointers. Rody (man behind Groovy) has been around a long time and is not afraid to answer e mails or phone calls. He also has some videos posted on youtube.Are you working with tig for framebuilding? Originally Posted by zipzitQuestion.. I've looked long and hard on the web trying to find photos of TIG nirvana. Here's what I came up with...ref: http://waltworks.blogspot.comWaltworks Bicycle ForkI really am not getting this. My practice beads look like really good stick welding beads.. but too large for TIG stuff. I'm not really clear on how Walt (of Waltworks Cycles, welder of that bicycle front fork) is getting these beads. Is that a step and pause motion, or is that bouncing on the footpedal or even a machine pulser function.. ? (I'm pretty sure it's not the machine pulser, as Walt has been pretty verbal against that practice in the past.) When you look at a practice TIG bead (initially with NO Filler) how do you judge what is good? On a scale of 1 to 10, how important is:Consistency of 'bead' width?the overall width of bead (too narrow? too wide?)stacked dimes / stepped look to the 'bead'size of the heat affected zone?penetration as evidenced by view of the backside of a piece of metal?consistency of bead itself (cleanliness, no holes, voids, signs of inclusions..)I think for me welds like that bicycle front fork are the ultimate goal.. Do you guys agree? Does anyone have a photo of a better tig bead on steel as a target goal of TIG nirvana? I'm reducing my variables to focus on one thing at a time, I'm just not sure which of the above elements I should be focusing on. I do realize I'm in for a long, long haul. I'm trying to focus on a consistent narrow width bead, and that means a very small weld gap (causing me to frequently contaminate the electrode.) I will say I'm getting VERY adept at using the grinder, so much so that I have now been able to sharpen 1/8" drill bits by hand very successfully. (I've been doing lots of pilot drilling in 3/4" steel on the table project.)Thank you for your input!--zip
Reply:Hey Zip,I'm just starting out as well and your work looks very familiar :-) Keep it up you're progressing great.
Reply:That red stuff is from contaminating your tungsten and running way too hot. But our photos show good progress so keep up the practice your going in the right direction. |
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